(a) Field of the Invention
The present invention relates to a radio frequency switch, a method of controlling the same, and a radio frequency identification smart shelf system.
(b) Description of the Related Art
In general, in a radio frequency identification (RFID) system, a tag is attached to an object, and a reader recognizes an intrinsic identifier of the tag that is attached to the object, and thus various services such as positioning and remote processing and management of the object and information exchange between objects can be provided. Such an RFID system is a non-contact recognition system and thus does not require direct contact of a reader to a tag or to scan in a visible band. Thereby, an RFID system is evaluated as technology to replace a barcode, which is a contact recognition system, and a use range of the RFID system has been increased.
The RFID system uses several frequency bands, such as a low frequency (30 kHz-500 kHz), a high frequency (850-950 MHz), or 2.45-2.5 GHz. An RFID system of a low frequency band may be used at a short distance of 1.8 m or less, and an RFID system of a high frequency band may be used at a far distance of 10 m or more. That is, the RFID system recognizes information of a tag within several meters by connecting an antenna to a reader and processes data thereof.
Such an RFID system is widely applied to a smart shelf. In an RFID smart shelf system, by applying an RFID system to a shelf that uses in a display stand or a product warehouse, a reader recognizes a tag that is attached to a product that is put on the shelf and provides information about the product to a user, and thus real-time stock management is easily performed. However, when a tag is attached to a product in which tag data recognition is weak like a metal or a liquid or when a weak radio area occurs due to a dense environment between tags, if a reader recognizes a plurality of tags that are exhibited on a smart shelf, a tag in which recognition is omitted may occur. In order to solve such a problem, conventionally, in some application fields, a method of shaking a product to which a tag is attached is suggested, but the shaking method cannot be used to a product that is exhibited in a smart shelf such as medical supplies.